There have been several [1]}, [2]}, [3]}, [4]}, [5]}, [6]}
lattice calculations for \(\kappa _{\scriptscriptstyle E}\)  in a gluonic plasma, estimated from the
\(EE\)  correlator. All these works use a model of \(\rho _T(\omega )\)  to extract
\(\kappa _{\scriptscriptstyle E}\)  from the \(EE\)  correlator. We know the form of \(\rho _T(\omega )\)  at very
high and low energies: it approaches the perturbative spectral
function at very high \(\omega \)  and a dispersive form \(\sim \kappa _{\scriptscriptstyle E}\omega \) 
in the infrared. For intermediate values of \(\omega \) , different
calculations use different models. The calculations also differ in how
they renormalize the lattice correlators. The left panel of Fig. REF 
shows the results for \(\rho _T(\omega )\)  obtained at 1.5 \(T_c\)  in a recent
calculation [6]} when using different models (stylistically I have
followed here a similar plot of an earlier calculation[2]}).
The right panel of Fig. REF  shows a compilation of the results
obtained in these calculations, in the 1-4 \(T_c\)  range. To reduce clutter,
where the same group has published two calculations, I have only kept the
new one. There seems to be a good agreement between the different
calculations, within the large error bars (which are dominated by
systematics: the effect of using different models of \(\rho _T(\omega )\) ).
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